Selective Reduction in the Nicotinic Acetylcholine Receptor and Dystroglycan at the Postsynaptic Apparatus of mdx Mouse Superior Cervical Ganglion

• Published in: Journal of neuropathology and experimental neurology 2000-02, Vol.59 (2), p.103-112
• Main Authors: ZACCARIA, M LETIZIA, DE STEFANO, M EGLE, GOTTI, CECILIA, PETRUCCI, TAMARA C, PAGGI, PAOLA
• Format: Article
• Language: English
• Subjects: Animals; Biological and medical sciences; Comparative analysis; Cytoskeletal Proteins - metabolism; Diseases of striated muscles. Neuromuscular diseases; Dystroglycans; Dystrophin; Dystrophin - genetics; Dystrophin - metabolism; Ganglion; Immunohistochemistry; Medical sciences; Membrane Glycoproteins - metabolism; Mice; Mice, Inbred C57BL; Mice, Inbred mdx; Nerve Crush; Neurology; Protein Isoforms - genetics; Protein Isoforms - metabolism; Receptors, Nicotinic - metabolism; Superior Cervical Ganglion - chemistry; Superior Cervical Ganglion - metabolism; Superior Cervical Ganglion - ultrastructure; Synapses - chemistry; Synapses - metabolism; Time Factors; Utrophin
• ISSN: 0022-3069; 1554-6578
• DOI: 10.1093/jnen/59.2.103

Our previous data suggested that in mouse sympathetic superior cervical ganglion (SCG) the dystrophin-dystroglycan complex may be involved in the stabilization of the nicotinic acetylcholine receptor (nAChR) clusters. Here we used SCG of dystrophic mdx mice, which express only the shorter isoforms of dystrophin (Dys), to investigate whether the lack of the full-length dystrophin (Dp427) could affect the localization of the dystroglycan and the α3 nAChR subunit (α3AChR) at the postsynaptic apparatus. We found a selective reduction in intraganglionic postsynaptic specializations immunopositive for α3AChR and for α- and β-dystroglycan compared with the wild-type. Moreover, in mdx mice, unlike the wild-type, the disassembly of intraganglionic synapses induced by postganglionic nerve crush occurred at the slower rate and was not preceded by the loss of immunoreactivity for Dys isoforms, β-dystroglycan, and α3AChR. These data indicate that the absence of Dp427 at the intraganglionic postsynaptic apparatus of mdx mouse SCG interferes with the presence of both dystroglycan and nAChR clusters at these sites and affects the rate of synapse disassembly induced by postganglionic nerve crush. Moreover, they suggest that the decrease in ganglionic nAChR may be one of the factors responsible for autonomic imbalance described in Duchenne muscular dystrophy patients.